[ExI] extropy-chat Digest, Vol 90, Issue 29

[Stefano Vaj]

On 26 March 2011 18:54, Adrian Tymes <atymes at gmail.com> wrote:
> More importantly, how much of it does any private venture - or even NASA -
> have ready access to today?  (Remember, it's been discovered that the
> Saturn rockets could not be rebuilt today, due to loss of knowledge and
> parts; you'd have to redevelop those entirely.  Same thing applies here.)

I am afraid you may have a point here. :-(

Speaking of technological exponential curves... :-)

>> The fuel is already stocked in strategic arsenals, and
>> has already been paid for.
>
> By agencies with no intention of using them for this venture, in forms that
> are not well suited for this venture.  You'd have to buy it and reprocess it.

Agreed. In fact, everything is just a hypothetical in the present
circumstances. But things have the habit of changing quickly, and in
any event no harm involved in learning that "we could, if we really
wanted"...

>> And by no means you are easily taking thousands
>> of tons out of the earth gravity wells with chemical rockets...
>
> Irrelevant.  There's plenty of mass inside Earth's gravity well.  (BTW,
> that's "well", singular, since you're talking about one planet.)

Mistype. What I am trying to say is that you are not likely ever to be
putting large-scale space-based solar power in place with chemical
rockets. Could we break even, with a predetermined number of Project
Orion propulsion launches, if somebody ever dared to do it before it
is too late?

-- 
Stefano Vaj